This paper proposes a simple modification of the Black–Scholes model by assuming that the volatility of the stock may jump at a random time τ from a value σa to a value σb. It shows that, if the market price of volatility risk is unknown, but constant, all contingent claims can be valued from the actual price C0, of some arbitrarily chosen “basis” option. Closed form solutions for the prices of...

The availability of intraday stock/index return in the web facilitates the improvement of return volatility estimation over the traditional method that is based on inter-day return data. Truncated Levy process distribution is used to extract the intraday return distribution parameters. The calibration to the volatility for Black-Scholes option pricing is studied using the data from Levy-Gaussia...

investing in stock markets usually is involved in more risks than the bounds and bank deposits. it is expected that resulting returns (capital gain plus yields) from trading in a stock market to be more than those of in a risk free investment. therefore, developing accurate techniques of estimation and forecasting in volatility analysis of financial markets is inevitable. sum squares of weekly ...

This paper explores the role of monetary policy in a segmented stock market model. Previous research (e.g Mankiw and Zeldes (1991), Vissing-Jørgensen (2002)) reports that only a fraction of the households participates in the stock market. In this paper participating households have stochastic dividend as part of their income and are, therefore, subject to financial market risk. Also, only parti...

This note explores the behaviour of the implied volatility of a European call option far frommaturity. Asymptotic formulae are derived with precise control over the error terms. The connection between the asymptotic implied volatility and the cumulant generating function of the logarithm of the underlying stock price is discussed in detail and illustrated by examples.

In this work, I address the issue of forming riskless hedge in the continuous time option pricing model with stochastic stock volatility. I show that it is essential to verify whether the replicating portfolio is self-financing, in order for the theory to be self-consistent. The replicating methods in existing finance literature are shown to violate the self-financing constraint when the underl...

When there is uncertainty about a CEO’s quality, news about the firm causes rational investors to update their expectation of the firm’s value for two reasons: Updates occur because of the direct effect of the news, and also because news leads investors to update their assessment of the CEO’s quality, which changes expected future cash flows. As a CEO’s quality becomes known more precisely over...

We use Bayesian Markov Chain Monte Carlo methods to investigate the linkage between the volatility of ethanol security prices and the uncertainty surrounding the profitability of ethanol production and the price variations of non-ethanol energy securities. The joint evolution of return and volatility is modeled as a stochastic process that incorporates jumps in both return and volatility. While...